Propeller



April 28, 1925.

F. BRACCO PROPELLER n013:2inra-2 Filed May 29, 1922 Patented Apr. 28, 1925.

UNITED STATS FREDERICK BRACCO, 0F LYNDI-I'IZTRST,` NEW JERSEY.

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Original application filed May 29, 1922, Serial No. Divided and this application Ied To all whom it may concern .1 y

Be it known that l, Fnnnniucit Biiaoco, a citizen ofthe United States, and resident of Lyndhurst, county of Bergen .and State of New Jersey, have invented certain new and useful Improvements in Propellers, of which the following is aspeciiicaton.

My invention relates to propellers and has for its object to provide a novel and simple construction and arrangement in which the propelleris capable of being readily folded to an inoperative position when its services are not required. Other more specific objects of the invention will appear from the description.hereinafter and the features of novelty will be pointed out in the appended claims. This application Vis a division of another application for a propeller iiled by me inthe United States Patent Office on May 29, 1922, SerialNo. 564,434, patented April 22, 1924 No. 1,491,512.

1n the accompanying drawfngs, which show several examples of the invention without defining its limits Fig. 1 is an elevation partly in section showing the invention with the parts occupying operative positions; Fig. 2 is a fragmentary section showing the propeller in a folded, in operative position; Fig. 3 is a section on the line 34-3 of Fig. 2 and Fig. 4 is a similar View on `the line 4-4 of Figul. I

In the forinillustrated in the drawings theblades 10 are carried by a plurality of sleeves rotatably mounted upon the propeller shaft and upon each other; `that is to sayy the blades 10 are mounted respt-ictively upon an inner sleeve 11 rotatable upon the hollow shaft 12, an intermcdiatesleeve 13 ro*- tatable upon the sleeve 11 andan outer sleeve 14 mounted to rotate upon the sleeve 13 as shown in Figs. 1 and 2. are so arranged upon the respective sleeves asto occupy the relative positions required to constitute an operative; propeller when said blades are unfolded, and so as to be capable ofjbeing rotated into surface` engagement with each other inafolded, inoperative position. That is to say the inner1 sleeve 11 and its blade 10 are fixed upon the hollow shaft12 for instance by .means of a key 15 while the sleeves 13 and 14 are each -capable of being rotated about their com# mon axis to fold their blades 10 into engage ment with the first-mentioned blade 10 and with each other' and to unfoldfsaid blades The blades 10 564,413.4Patent No.'1,491,512, dated April 22, 1924. May 17, 1923. Serial No. 639,576.

to an operative position; any suitable means Y may be utilized for actuating the sleeves to 10 at the proper points, said sleeves may 1 be. provided with pins 16 which extend into recesses 17, the opposite closed ends of which provide stops against which said pins abut.

The blades 10 may be locked in their operative and inoperative positions inany convenient way; in the illustrated example the. locking means comprises an auxilary shaft 18 located within thehollow shaft 12 and provided at its outer end with a head 19 which in turn carries one or more locking members 20. The latter cooperate with one or more apertures 21 with which the sleeves 11, 13 and 14 are provided, said apertures being so located as to register with each otherin the operative and inoperative positions of the blades 10 as shown in Figs. 1 and 2; that is to say the locking members 20, by projecting throughV the registering apertures 21, as illustrated in Figs. 1 and 2, prevent rotation of sai d sleeves relatively to the shaft 12 and to each other and thus `lock saidv blades 10 in either and both of position Ato enter said apertin'es in either position of the blades 10. The mechan'sm whereby the auxiliary shaft 18 is adjusted relatively to the hollow shaft 12 to shift the locking members 20 into and out of said apertures 21 may be of any convenient type; for instance, as shown in the illustrated eX- ample, an internally threaded hand wheel 22 Inay be rotatably mounted upon the hol-l low shaft 12 in a manner to be incapable of axial movement relatively thereto, in which case the inner end of the auxiliary shaft 18 is screwthreaded, as indicated at 23, for cooperationwith saidhand wheel 22. In the present instance the hollow shaft12 is fixed against lengthwise movement by means of collars 24 and a flange 25 fixed upon the stern 2601' the vessel; a gear 27 is mounted Cil man

upon the hollow shaft l2 for operatively connecting the same with a source of power.

In practice the hand wheel is rotated in a direction to shift the shaft lengthwise of the shaft 12 to withdraw thelocking members 2O from the apertures 2l and permit the folding and unfolding of the blades 10 under which said wheel 22 is operated in the reverse direction to again Y.shift said locking members 2O into said apertures 2l and thereby lock said blades l() in whatever position they may occupy at the time.

It will be obvious that if desired the'numbei' and arrangement of blades upon'a given sleeve, may be otherwise than as shown without in anyway departingfrom the spirit of the invention. :In their fold-edinoperative positions, in which the bladeslO lie in approximately surface engagement with each other,'the group of blades rotatably drop, by gravity, to a position in line with the rudder of the ship and thus offer a minimum of resistance to the progress of the vessel when the latter is, for instance, under sail.

The invention is simple in construction and efficient in operation and provides an arrangement whereby the propeller blades may be easily adjusted from an operative to an inoperative positionand' vice versa in a minimum of time and with comparatively little effort. The invention is particularly adapted for use in vessels pro-V vided with both sail and power and permits the propeller to be quickly folded when the f ship is operating undei sail thus elimiiiating drag and other objectionable features tending to interfere'with the progress of the The illustrated and` described, prof vessel. peller arrangement may be also utilized in connection with aeroplanes and airships and anywhere else where a folding propely ler is desirable.

The principal purpose of the invention is to provide a propeller construction in which the i'nopellers are capable of convenient and practical adjusti'nentiu a n'ianner to make them dependal'ile.v for intermittent periods' of service and so as tozhave theirbull;A so reduced or removed when not in use, as to reduce oreliminate the drag without requiring a complete dismantling of the propellerl and its associatedlnarts.

same.y

It may be stated that the invention is especially useful in that it providesa novel rand efficient means lwhereby close maneuvering is possible, at will, either with-sail or power alone orwith both sail and power.

`vessels,

ItY will be understood that the illustrated enamplel is intended to exemplify the invention without arbitrarily restricting the elements thereof' or the construction .and operation y of. the' itsaees This introduces intoships drills a new ele` ment and with it a new set of tactics which V*will assist materially in veering and navi` gating in closequarters-.and prove of great usefulness in also imparting to ships or for intermittent stretches under proper conditions, the advantage of propulsion by a combination of sail andl power. 'All of the above willffurther result in increased speed of travel, with an increased average speed-thus reducingthe time of travell from port to port, providing agreater control of the factors of navigation and av maximum operative economy.

Various changes in the f specific forni shown and described may be made within the scope of the claiins,-witlioiit departing from the spirit of -m'yinvention.

I claim:

1.Tlie combination of a` shaft, a plu-rality of propeller blades mounted thereon and located in a common circumferential plano, said blades being rotatably adjustable relatively to each other toafelded inoperative Vposition in which Vall lof said blades extend in the same direction and lie contigiaous to each other and to an unfolded operatiif'e position and means'fforlocking saidv blades in either position.

2. The combination of a hollow sha-ft, a plurality of collars rotatably mounted upon said shaft and uponea'eh other,-propeiler blades carried by said collars and located in a common circumferentialfplane, said blades being adjustable'by said collars, iu said common plane, to an unfolded, operative position and toa v:folded inoperative position and means located 'partlywithin said hollow shafftffor'locking saidblades -in either position.

3. The combination of a hollow shaft, a plural-ity of collars rotatably mountedv upon saidV -shaft and `upon each other, propeller blades carried by said -collars yand llocated tive position-and to a folded ini'ipeia'tivi-x position, ysaidcollarsbeing provided `-with apertures"adapted -to 'register with' each other yin eac-h position of theblades, an auxiliary shaft slidably-mounted within said hollow shaft, ahead carried by Isaid ausiliary shaft,lo`cking members projecting from said headl and-adapted -to enter -saidA apertures tolock 4said vblades-in either position and means wherebyV saidI aiuiiliary shaft is yslidably actuate'dto shift said locking menibers intoand out ofsaidapertures.

In testimonywhereofv Iihave signed this specification.

FREDERICK. BRACCO. 

